(n.) An optical instrument for forming and examining spectra (as that of solar light, or those produced by flames in which different substances are volatilized), so as to determine, from the position of the spectral lines, the composition of the substance.

Cassegrainian telescope Newtonian telescope OAO OSO astronomical observatory astronomical telescope chromatoscope coelostat coronagraph coronograph heliostat kaleidoscope observatory orrery oscilloscope periscope planetarium radar telescope radio observatory radio telescope reflector refractor spectrograph spectroheliograph spectrohelioscope stereoscope telescope